Answer:
A and C
Step-by-step explanation:
solving the equations
A
x² - 4 = 0 ( add 4 to both sides )
x² = 4 ( take square root of both sides )
x = ±
= ± 2 ← required solution
B
x² = - 4 ← has no real solutions
C
4x² = 16 ( divide both sides by 4 )
x² = 4 ( take square root of both sides )
x = ±
= ± 2 ← required solution
D
2(x - 2)² = 0 , then
x- 2 = 0 ( add 2 to both sides )
x = 2 ← not the required solution
Answer:
x = 15
Step-by-step explanation:
The sum of the 3 angles in a triangle = 180°
Sum the 3 given angles and equate to 180, that is
3x - 10 + 6x + 5 + 4x - 10 = 180, simplify left side
13x - 15 = 180 ( add 15 to both sides )
13x = 195 ( divide both sides by 13 )
x = 15
Answer:
The value is 27
Step-by-step explanation:
The answer would be (x+1)(x+3)
You might have to do the quadratic formula